Biology Worksheet 1

1. What is the purpose of science?
The purpose of science is to understand. With science, we ask questions, seek answers, and prove or disprove our theories and speculations. According to the text on page 10 “Science is a way of knowing about the natural world.” (Citations will be provided at the end of the worksheet, rather than a continuous re-pasting each time.) 2. Define organism. Give an example of a unicellular organism.
According to the text on page 3, “Organisms, such as trees and humans, are a collection of organ systems.” The Cardiovascular system is one such organ system, as is the Nervous System, both of which comprise part of animal life. On the same page, the text specifically lists bacteria as an example of a unicellular organism, therefore the H. pylori bacterium listed in Section 1.3, page 11 is a specific example of a unicellular organism.

3. Identify the 3 domains of living things. Which domain contains multicellular organisms? (2 pt)
The three domains listed in the text on page 7 are Bacteria, Archaea and Eukarya. Multicellular organisms comprise the Eukarya domain

4. List the four kingdoms of Eukarya.
As illustrated on Figure 1.6 on page 7 of the text, the four kingdoms of Eukarya are Protists, Plants, Fungi and Animals. They are also described as Plantae, Fungi, Animalia, and Protista on page 8. 5. List and give a brief explanation of the steps of the scientific method.
The steps are Observation, which is self evident. One watches, gathers and studies data, some questions may be answered, others will arise. From these initial observations a Hypothesis will arise. A Hypothesis may be described as a sort of educated guess or question even, one which requires additional information to test accurately. One I come back to is the old hypothesis involving decomposition which challenged the widely held belief of spontaneous generation. The next step is more observation and experiments aimed at testing the validity of the hypothesis. After this stage is the Conclusion in which the results of the experiments either support or reject the hypothesis (although Figure 1.8 on page 10 of the text shows that, as is often the case, conclusions may be drawn without experimentation). Finally, after many tests and experiments a Scientific Theory is established, such as the Theory of Relativity.

6. Give an example of a control group and an experimental group being used in the same experiment.
In such an experiment a large group of similar individuals would be randomly, yet evenly, separated into two groups. For this example I will use cough syrup. Both groups will have similar symptoms traced to the common cold virus. The experimental group will receive a dosage of test medication to test its effectiveness in lessening the symptoms, while the control group will believe they are receiving the same medication, but would instead receive what is commonly referred to as a placebo. Members of neither group will know which division they belong to, and indeed may not even realize there is even a control group at all. The placebo, for best results will taste and appear similar to the actual medicine (not hard since it all tastes horrible). 7. Two scientific studies have different probability values associated with their results. Study A has p = .005 whereas Study B has a p = .02. Which study shows the greater confidence level that the results were not due to chance? Explain your answer.
Study A, because the number .005 (or 5 thousandths, or half of one percent) is less than .02 (or two hundredths, or 2 percent). In the formula p = x, p represents the probability that the results are due to chance, randomness or sheer luck (chaos). The lower the number x, the greater the chances may be reproduced under similar circumstances. From a mathematical standpoint however, half of a percent is significantly less than two percent. 8. What URL's should you look for on the internet when trying to find a website with reliable scientific information? Why? Which types of URL's should you carefully question and verify? Why? (2 pts)
I question, as a matter of prudence, EVERYTHING I find on the Internet regardless of its source. The primary reason for this is that, as evidence by current education, those things I learned 30 years ago in school have drastically changed from what is being taught today. However, in order to answer this question appropriately, any URL that has a .edu or .gov appending it is generally considered reliable. These sites originate with educational and governmental institutions, respectively (however the .gov designation is specific to the United States). Sites with .org appended are generally non profit, however, .com or .net usually denote a for profit site. Because of my degree pursuit in Computers, this information is considered common knowledge for me, however it is found on page 14.

9. What is anecdotal data? Why is it considered unreliable supporting scientific information?
Page 14 lists anecdotal data as that which is comprised of the testimonials of individuals. It is unreliable because it does not consists of results from scientific study, but moreover because of human tendency to embellish, exaggerate or “go along with the crowd”. It is the equivalent of asking someone “How do you feel?” rather than drawing blood to run for possible infection. 10. Why is correlation data (data showing that two events occurred at the same time) unreliable?
Pulling on my recent Logic course, this helps me explain this better. It is not true that because of A + B = C, then A always leads to C. Page 14 lists exposure to cold and getting a cold. Laying butt naked in the snow (though not entirely acceptable as a mode of behavior) will not cause you to get a cold. Nor will someone sneezing near you cause you to be sick. Both may lead to the same result, but are different causes and different mechanisms. Indeed, because of the commonly held belief that a virus mutates constantly from vector to vector not every instance of exposure to it will be the same. 11. Briefly define the following: matter, element, atom, molecule. (3 pts).
Matter is everything, and everything is composed of matter. Page 21 describes matter as anything that takes up space and has mass. Elements are described as “one of the basic building blocks of matter” which “cannot be broken down by chemical means (Section 2.1, page 21). Uranium is an element, isotopes of which are broken down in nuclear reaction such as fusion and fission. Atoms are the smallest unit of measurement applicable to an element, anything smaller than an atom of Uranium, is simply the individual components which have their own characteristics. In my example of fusion and fission, it is their destruction (either through forcing the atoms together, or breaking them apart) that releases the tremendous amounts of energy we see. An atom of Iron would have the same effect, however Uranium is unstable enough to allow this reaction to occur slightly easier (if you can describe it as that).
A molecule is the combining of two or more atoms, from separate elements, to form a entirely different substance. A popular example is water, with consists of two Hydrogen and one Oxygen atoms. Both Hydrogen and Oxygen are gases in their natural state, and their liquid state is destruction due to the extreme cold temperature at which it must be maintained. When combined, their nature alters to form water.

12. What are the subunits of atoms and what is the electrical charge of each?
The subunits of an atom are the proton, which as a positive charge, the neutrons which are neutral or uncharged, and the electrons which carry a negative charge. Page 21 lists these as the best known, which leads one to conclude there are other subunits as well. 13. An ion is an atom or molecule that has a (full) positive or negative charge because its number of electrons and protons is not equal. Give an example of an ion.
Hydrogen Peroxide would be an ion, because water is a neutral charged molecule consisting of one Oxygen atom per two Hydrogen, known as H2O. Hydrogen Peroxide is simple 2(HO) or H2O2, or two Oxygen atoms and two Hydrogen atom. Because it contains one extra Oxygen atom, it would contain a negative charge rather than neutral (and accounts for its chemical reaction when it comes into contact with organic matter). 14. What are isotopes?
According to the text on page 22, isotopes are an element that contains “the same number of protons”, but varying numbers of neutrons. While this change does not alter the Atomic Number, it does change the mass of the element. The most popular known isotopes are radioactive elements, such as Uranium. Isotopes of Uranium have varying uses, the isotope that is used for Nuclear Power, is different from that used by Nuclear Weapons.

15. What are polar molecules?
Water is a polar molecule, described in the text on page 25 as the atoms comprising it have different polarities; Oxygen being slightly negative and Hydrogen being slightly positive. This is because of the attraction of the atoms, they take on a slight charge of the other atoms comprising the molecule.

16. List two ways that a covalent bond differs from a hydrogen bond. (2 pts)
Atoms are structured similarly to a Solar System, with the Nucleus being at the center, and the electron shell being the symbolic equivalent of orbiting planets. In an Ionic bond, atoms which have more than one shell (or orbit) are most stable “when their outermost shell contains eight electrons” (23). Ionic bonds occur when atoms containing opposite charges are drawn together, such as in salt. In ionic bonding, an electron is basically transferred to the other atom, forming the bond. Covalent bonding, however is different because the atoms share the electrons, each atom contributes one or more electrons to the bond with the text on page 24 giving the example of a handshake. Apart from sharing electrons, rather than transferring one from the other, the other difference appears to be the fact that ionic bonding results in a polarity while the covalent bonding results in a neutral charge.

17. If a solution has a pH of 2, would it be considered acidic, basic or neutral (pick one).
According to figure 2.10 on page 28 ph 2 is acidic, and the equivalent of stomach acid or lemon juice (I always thought stomach acid would be stronger…) 18. What is the function of a buffer?
The function of a buffer is to serve as a form of homeostasis, to prevent the ph value in an organism or ecosystem from becoming off balance, as described on pages 28 and 29 in the text.

19. What is the difference between a dehydration reaction and a hydrolysis reaction?
According to page 29 of the text, in a dehydration reaction, hydroxyl group and a hydrogen atom are removed (forming water, hence “losing water”)and the resulting macromolecule forms. In a Hydrolysis reaction, the opposite occurs; water is taken on and broken down, the resulting hydrogen atom and OH molecule are added resulting in breaking down the macromolecule. (Water acting as a solvent?)

20. Define organic molecules. Give an example.
An organic molecule is one that contains carbon and hydrogen. Glycogen, a form of sugar is an example. (Pages 29 and 30).

21. List a) the 4 general types organic macromolecules. Then list b) the macromolecule's general function. Then list c) a specific type of each macromolecule. (3 pts)
From pages 30 – 40:
Carbohydrates, “for quick and short term energy storage” an example of which would be Glycogen, Fructose or Starch.
Lipids, which function as long term energy storage. Examples of which include Olive Oil, Animal Fat (bacon grease is my personal favorite) and commercial bought Crisco (yumm).
Proteins, which “form the structure and function of cells”. Collagen (Jell-O) is an example of a protein that assists in the skeletal and muscular system while antibodies help with our immune system, such as with white blood cells. Different types of proteins serve different functions, but protein in the diet is able to be remanufactured into the various types needed by the body through chemical breakdown and reorganization. 22. Lipids are a diverse group of macromolecules that do not dissolve in water. List three classes of lipids.
From the text, the three types are Fats/Oils, Phospholipids, and Steroids

23. The building blocks of proteins are amino acids. What are the covalent bonds between amino acids called?
Page 37, Peptide Bond 24. What is the role of ATP in our bodies?
According to figure 2.25, page 40 “ATP is the universal energy carrier of cells.” When ATP breaks down, the energy released is used by the cells to form macromolecules, muscular contraction and the transportation of nerve impulses.
Works Cited:
Mader, Sylvia S., Windelspecht, Michael. Human Biology. Ed. 13th. p. 25-27